Messages in this thread | | | Date | Mon, 10 Jun 2013 19:29:46 +0200 | From | Lars-Peter Clausen <> | Subject | Re: [PATCH v2 3/6] dma: Add a jz4740 dmaengine driver |
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On 05/30/2013 08:46 PM, Lars-Peter Clausen wrote: >>> +static int jz4740_dma_alloc_chan_resources(struct dma_chan *c) >>> +{ >>> + struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c); >>> + >>> + chan->jz_chan = jz4740_dma_request(chan, NULL); >>> + if (!chan->jz_chan) >>> + return -EBUSY; >>> + >>> + jz4740_dma_set_complete_cb(chan->jz_chan, jz4740_dma_complete_cb); >>> + >>> + return 0; >> Sorry, I didnt reply on this one. The API expects you to allocate a pool of >> descriptors. These descriptors are to be used in .device_prep_xxx calls later. > > The size of the descriptor is not fixed, so they can not be pre-allocated. And > this is nothing new either, most of the more recently added dmaengine drivers > allocate their descriptors on demand.
Vinod, are you ok with this explanation?
- Lars
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